It is proved that the Cartesian product of an odd cycle with the complete graph on 2 vertices, is determined by the spectrum of the adjacency matrix. We also present some computational results on the spectral characterization of cubic graphs on at most 20 vertices.
OBJECTIVE Atrial fibrillation is the most common arrhythmia after cardiac surgery. Several studies have shown the impact of vitamin D on heart disease; however, there have been few studies for the incidence of AF and its relationship with vitamin D levels. According to the different results of these studies, we decided to evaluate the relation of plasma… (More)
Let G be a graph of order n and let µ be an eigenvalue of multiplicity m. A star complement for µ in G is an induced subgraph of G of order n − m with no eigenvalue µ. In this paper, we study maximal and regular graphs which have K r,s + tK 1 as a star complement for 1 as the second largest eigenvalue. It turns out that some well known strongly regular… (More)